Base64 编码和解码

使用 std.base64.standard encode 将字节切片编码为 base64 字符串，并使用 standard decode 对其进行解码。

const std = @import("std");
const print = std.debug.print;
const Encoder = std.base64.standard.Encoder;
const Decoder = std.base64.standard.Decoder;

pub fn main(init: std.process.Init) !void {
    const allocator = init.gpa;

    const src = "hello zig";

    // Encode
    const encoded_length = Encoder.calcSize(src.len);
    const encoded_buffer = try allocator.alloc(u8, encoded_length);
    defer allocator.free(encoded_buffer);

    _ = Encoder.encode(encoded_buffer, src);
    try std.testing.expectEqualStrings("aGVsbG8gemln", encoded_buffer);

    // Decode
    const decoded_length = try Decoder.calcSizeForSlice(encoded_buffer);
    const decoded_buffer = try allocator.alloc(u8, decoded_length);
    defer allocator.free(decoded_buffer);

    try Decoder.decode(decoded_buffer, encoded_buffer);
    try std.testing.expectEqualStrings(src, decoded_buffer);
}